1. Field of the Invention
The present invention relates to a production management technology, specifically to a technology that is effective when applied to excess inventory management, control and other such manipulation of components in production planning systems such as MRP (Material Resource Planning).
2. Description of the Related Art
In manufacturing processes of various products, the appropriate procurement of a variety of components that constitute the products is essential for the promotion of efficiency in the manufacturing processes.
For that reason, it is known that by employing an MRP technology such as that disclosed in Patent Document 1, a component procurement plan is prepared in line with the production plan of products, and the components can be distributed appropriately every week for example. It is also known that excess components are distributed to each of the manufacturing processes at the time of production plan preparation.
However, in actual manufacturing processes, various factors cause actual product quantities to vary from the product quantities specified during production plan preparation. For that reason, where the most suitable component distribution is performed on the basis of MRP every week, if excess components are produced within the period between production plan preparation and preparation of the next production plan and those components are of no use, the components become excess inventory.
In MRP, additionally, although the weekly most suitable result is output, factors causing the excess inventory are not considered at all. If a large number of components are used in every product and there is a deep hierarchical structure of inter-component dependency, appropriate control of such components of no use would not be feasible.
One possible solution to prevent the excess inventory of components is to prepare, for example, a daily or hourly production plan, which is a shorter time period than a weekly production plan; however, this is impossible in practice because the amount of information and calculation required for such production plan preparation is huge, and the procurement of components is quite complicated.
In the existing production management system in particular, a manager has to place orders for components trusting the production plan that is updated every week by MRP, and in cases such as when there is a large variety of components, a lengthy hierarchy of BOM (bills of material), and many common components, tracing the factor causing the excess components can be difficult if the excess components are included in the inventory assets, and making the decision of whether to hold or discard the components requires some time.
Patent Document 1 discloses a technology for pursuing a low cost and real-time production management system by constantly generating expansion constitution information that is the expansion of required quantities of each article number for each instructed article number, on the basis of component information representing information of a single article number, component table information representing the relationship between article numbers, and application information representing alterations in article numbers to be applied to a product.
Patent Document 2 discloses a technology for efficiently managing a design process for preparing the technical information of a drawing and the like by displaying the issue result of a drawing as a progress picture for each kind of machine of the product in accordance with a drawing issue plan set so as to procure parts on the basis of a production plan.
However, neither Patent Document 1 nor Patent Document 2 discloses the displaying of information required for analyzing the factors that caused the excess inventory of components.
Patent Document 1:
Japanese Patent Application Publication No. 2001-75629
Patent Document 2:
Japanese Patent Application Publication No. 2001-84020